1. Field of the invention
This invention relates to an amphibious vehicle, and particularly, an apparatus and method for retracting axle-driven wheels onboard such vehicle.
2. Description of Prior Art
Numerous amphibious vehicles have been designed and manufactured; the majority of these leave the wheels in place when the vehicle is water-borne, thereby limiting the speed of the vehicle through water.
U.S. Pat. No. 3,903,831 describes a vehicle having a retractable wheel-system to retract the wheels into cavities within the hull of the craft. This mechanism does not draw the wheels to a position fully above the waterline when afloat, but instead uses a complex mechanism to pivot the wheels to within the hull and to close a hatch over the opening of the wheel-cavities to reduce drag in the water. The pivoting apparatus of this design also of necessity requires chains as the drive-means; such chains require a higher degree of attention and maintenance than more dependable drive-axles, especially in the marine environment.
U.S. Pat. No. 4,958,584 discloses a pivoting mechanism which raises the wheels to a limited height where sliding panels may be employed to cover the openings into the hull. Again, the wheels are not raised above the waterline of the craft when afloat, and extra components and mechanisms are necessary to close the wheel-cavities in order to overcome the drag of the wheels in the water.
Consequently the need exists for an improved apparatus which will retract axle-driven wheels onboard an amphibious vehicle whereby they do not directly contact water while the vehicle is normally afloat, without need for covers or sliding panels to render them unobtrusive.
Accordingly it is the object of this invention to overcome the disadvantages of the prior art, or at least provide the public with a useful choice.